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Business Segments - Schedule of Other Specified Segment Disclosures (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Segment Reporting Information [Line Items]
Accretion of asset retirement obligations	$ 0.9	$ 0.9	$ 3.4
Deferred and noncurrent income taxes (benefits)	9.3	(1.4)
Additions to property, plant and equipment	90.9	64.0
Operating Segments | Marketing Segment
Segment Reporting Information [Line Items]
Accretion of asset retirement obligations	0.9	0.9
Deferred and noncurrent income taxes (benefits)	12.7	(2.0)
Additions to property, plant and equipment	86.9	60.8
Corporate and Other Assets
Segment Reporting Information [Line Items]
Accretion of asset retirement obligations	0.0	0.0
Deferred and noncurrent income taxes (benefits)	(3.4)	0.6
Additions to property, plant and equipment	$ 4.0	$ 3.2

X

- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

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-Topic 410
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Amount of deferred income tax expense (benefit) and income tax credits.

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Amount of expenditure for addition to long-lived assets included in determination of segment assets by chief operating decision maker (CODM) or otherwise regularly provided to CODM. Excludes expenditure for addition to financial instrument, long-term customer relationship of financial institution, mortgage and other servicing rights, deferred policy acquisition cost, and deferred tax assets.

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